"The spirit of a true convert is a spirit of faith and reliance on the power, wisdom, and mercy of God, and such a spirit is naturally expressed in prayer. True prayer is nothing else but faith expressed. Hence we read of the prayer of faith; James 5:15. True Christian prayer is the faith and reliance of the soul breathed forth in words. But a hypocrite is without the spirit of faith. He hath no true reliance or dependence on God, but is really self-dependent.
As to those common convictions and affections which the hypocrite had, and which made him keep up the duty of prayer for a while; since they are not reaching the bottom of the heart, nor being accompanied with any change of nature, a little thing extinguishes them. The cares of the world commonly choke and suffocate them, and often the pleasures and vanities of youth totally put an end to them, and with them ends their constant practice of the duty of prayer."
Excerpt taken from a sermon by Johathan Edwards titled "Hypocrites Deficient in the Duty of Prayer" from the book Sermons of Johathan Edwards © 2005 Hendrickson Publishers, Inc